Malaria infected red blood cell. Credit: NIAID
The headlines this week are bursting with grand claims that an experimental malaria vaccine can also kill 9 out of 10 cancer types. Don’t believe the hype, we’re not there yet.
Where did the news come from?
was published that showed a fascinating connection between a new malarial vaccine for pregnant women, and unique markers present on many cancer cells. Researchers were initially studying the unique role a molecule called chondroitin sulphate plays in malarial infection in pregnant women. This sugar molecule is abundant on the surface of placental cells and sticks to a protein, called VAR2CSA, on the nasty malarial parasite. The scientists thought they could use this interaction in a vaccine against the parasite.
The trouble with hype
The cancer breakthrough came when the team realised many cancer cells also express chondroitin sulfate on their surfaces. So could a vaccine targeted against the malarial protein VAR2CSA, be morphed into a cancer busting weapon?
The scientists tested the theory by adding a toxin to the sticky VAR2CSA molecule, and administering it to cancer cells in the lab. The results were good; the altered vaccine killed cancer cells and spared healthy ones. It also proved effective in mice with prostate cancer, lymphoma and melanoma.
This all sounds great, so what’s the problem?
Malarial parasites infecting red blood cells Credit: Ed Uthman
It’s a welcome development, but it’s not a cure for 9 out of 10 cancer cells. It’s true that in the cancer cells the researchers were looking at, 95% of them expressed chondroitin sulfate. This made the majority of them a target for the targeted toxin. However, their work did not include many other cancer types, so the figure is actually far from 9 out of 10 including ALL cancer types.
The research was also conducted on mice, and we’d need far more dedicated and stringent testing to establish safety and efficacy in humans. Success in the lab and an ability to target these cells doesn’t necessarily mean it’ll prove as potent in an actual patient. It is a great find however, and it could be a worthy addition to modern arsenal of cancer drugs. There were 198 million cases of malaria in 2013, so let’s hope it’s effective against that too.
Read more at Cancer Research UK